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Biomedical subjects

D B McCarn

Publications and source records attributed to D B McCarn.

8 recordsLinked to original sources
PubMed1990

A mathematical model of retrieval system performance.

There have been a number of major evaluations of the performance of retrieval systems against large full text and surrogate (bibliographic) databases. These evaluations have concentrated on the experimental determination of the Precision Ratio, the fraction of retrieved items that are relevant to an information request, and the Recall Ratio, the fraction of the total number of relevant items that were actually retrieved. While these measures have met with general acceptance, they have also generated much controversy. The purpose of this article is to review the results of several of the largest evaluations and to propose a simple model for the performance of such systems that may help explain the relationship between these measures and user behavior.

Evaluation Studies as Topic↗
PubMed1980

MEDLINE: an introduction to on-line searching.

MEDLINE is presented as a prototype for on-line bibliographic search systems. Creation of the data base, indexing language, and file organization are reviewed. On accessing the files, search logic is illustrated with a sample MEDLINE search. NLM's development of a document delivery system to complement its bibliographic retrieval system is discussed.

Abstracting and Indexing↗
PubMed1978

MEDLINE users, usage and economics.

The on-line services of the National Library of Medicine (NLM) have grown in terms of both numbers of institutions using the service and in terms of total service provided. About 10 billed institutions are added per month with a total of 675 such institutions at the end of 1977. Total searches have now reached 900 000 per year. NLM services account for about 45% of all the bibliographic searching in the US. The effect of prices has been significant.

Costs and Cost Analysis↗
PubMed1970

Planning for on-line bibliographic access by the Lister Hill National Center for Biomedical Communications.

Lister Hill Center is concerned with developing a computerized information system, with a data base consisting of an expanded Abridged Index Medicus, using part of a large computer system, and connecting this system to the TWX network. With this in view, a study was made of the demands on such a network, and a study of the SUNY network showed that on-line access more than doubled the use of the data base. Other alternatives to the TWX system are described.

Computers↗
PubMed1969

The biomedical communications network.

The Biomedical Communications Network (BCN) is the embodiment of the plans of the National Library of Medicine to provide improved information, document, and education services to the health community. The BCN also will be the "core" public service network to ensure the most expeditious delivery of health information and education products to a selected public. As such, utilization of communications satellites as well as other more common forms of telecommunications are planned. The library component of the Network will provide decentralized library services to medical libraries, medical schools, hospitals, MEDLARS Centers, local medical centers and individual medical practitioners. These decentralized services will be provided through an information network with its hub at the Bethesda, Maryland site of the NLM. The NLM intends that the library services network be a controlled rather than a permissive system. This simply implies that participation and access to the services of the system will be determined by the NLM. Planning has already progressed to the point where services to be provided can be enumerated.

Communication↗